Pubic louse
Pthirus pubis
- Order & Family
- Order: Psocodea, Family: Pthiridae
- Size
- 1.1 to 1.8 millimeters in length
Natural Habitat
Exclusively found on human hosts, primarily in the coarse hair of the pubic and perianal regions, but occasionally in eyelashes, eyebrows, armpits, or chest hair.
Diet & Feeding
Obligate ectoparasite that feeds exclusively on human blood several times a day.
Behavior Patterns
They are relatively sedentary, clinging to hair shafts with specialized crab-like claws. They do not jump or fly and are usually transmitted through close physical contact, particularly sexual contact. The life cycle consists of the egg (nit), three nymphal stages, and the adult.
Risks & Benefits
Risk to humans includes intense itching (pruritus) caused by an allergic reaction to their saliva during feeding, which can lead to secondary bacterial skin infections from scratching. They are not known to transmit systemic diseases but serve as markers for potential exposure to other sexually transmitted infections.